By 2020, an estimated 128538 new cases of breast cancer and 70223 deaths due to it, and an estimated 205496 new cases and 119097 deaths due to cervical cancer would occur in India, contributing to 29% and 30% of the global burden of cervical cancer and mortality.1 Currently, there is no national breast and cervical cancer screening program in India. The primary aim of this ongoing cluster randomized controlled trial, in urban slum women, aged 35-64 years, in Mumbai, India, is to investigate the efficacy of cancer education and screening, using affordable, sustainable and culturally acceptable techniques, i.e. Clinical Breast Examination (CBE) and Visual Inspection with 4% Acetic Acid (VIA), performed by trained female primary health workers (FPHWs) in the: 1) Early detection of breast and cervical cancer, 2) Downstaging of breast and cervical cancer, 3) Reduction in breast and cervical cancer mortality, 4) Reduction in cervical cancer incidence. The secondary aims of this trial are: a) To estimate the cost and resource needs for conducting community-based cancer education and screening for breast and cervical cancers by CBE and VIA, b) To study the behavioral, cultural and psychological factors affecting participation of women in such programs. The findings till now suggest that the trial is progressing well and as planned: a) the planned analysis of process measures supports clearly, the feasibility and acceptability; with excellent screening participation, and diagnosis and treatment compliance rates (these data have been published), b) We have an excellent mechanism for capturing the events in the screening and control groups, c) Significant downstaging of cervical cancer by VIA is already evident. The trial data safety and monitoring board (DSMB) has considered this, but decided that we should continue with the follow-up as planned, till we reach the required decision point. An interim data analysis has been suggested by the DSMB in its latest audit and is planned for early 2010. The progress of this trial to date clearly demonstrates the great potential of its results to guide breast and cervical cancer control policies not only in India but also worldwide. We anticipate that continued follow-up will result in the required number of endpoints being achieved. PUBLIC HEALTH RELEVANCE: This cluster randomized control trial, involving 151538 socially disadvantaged women (slum dwellers) aged 35-64 years, studies the efficacy of CBE and VIA based screening, performed by female primary health workers (FPHWs). The progress of this trial to date clearly demonstrates the great potential of its results to guide breast and cervical cancer control policies not only in India but also worldwide.